STI Geyer Istoric

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UST History

Excerpted from theHANDBOOK OF STORAGE TANK SYSTEMS AVAILABLE NOW

Wayne Geyer Executive Vice President

Steel Tank Institute

The means to store hazardous liquids has changed considerably since the discovery of oilin 1859. Wooden barrels were replaced by riveted steel tanks and eventually, welded steel storage tanks. Codes in the U.S. to regulate flammable liquids, and standards for

performance testing and construction, were developed in the first quarter of this century.

As the use of motorized vehicles became the most common mode of transportation,storage tanks were installed underground for reasons of safety, convenience, and aesthetics. Around World War II, galvanized tanks were replaced by primed or asphalt

painted tanks.

Between 1960 and 1970, the concern for lost inventory became a driving force to preventunderground steel storage tanks from corroding. Non-metallic tanks were developed.Shop-fabricated steel tanks were built with various forms of corrosion protection designthrough the use of plastic baggies, thick fiberglass reinforced coatings, and galvanicanodes in conjunction with coal tar epoxy coatings. Existing non-protected steel tankswere field upgraded with internal linings and impressed current cathodic protection.

Between 1970 and 1990, a strong concern for the environment further advanced thetechnologies used to safely store hazardous liquids underground. Secondary containment

became a desirable feature in tank design. Steel tanks were fabricated with a second wallof steel or with a non-metallic jacket made of FRP or HDPE. Thick urethane or FRPcoated tanks are popular without anodes. Over a quarter million underground sti-P3cathodic protected tanks have been installed in the U.S. alone since 1969.

Today, the industry in North America has experienced a further revolutionary change.Tank owners and operators in the non-service station sector are installing their liquid storage systems above grade. As the influence of fire safety and environmental codeofficials continues in the U.S. and Canada, secondary contained and fire resistantaboveground storage tanks have become very popular.

1. Past

The American experience of using steel tanks to store petroleum and chemicalsrepresents a microcosm of the efforts in countless nations. The story of that experiencecovers the earliest days of discovering how oil could change society for the better, and more recent times as environmental awareness and public-safety concerns have shown


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the compelling need to store the energy source safely.

Travel back in time about 140 years to Titusville, Pennsylvania, a small town where onan August day Americas first oil-well gusher erupted. Daniel Yergin, author of ThePrize, a book that chronicles the history of the oil industry, reports that the locals in

Titusville rushed tubs, wash basins and whiskey barrels into use to contain the black gold.

As the Industrial Age discovered more and more uses for petroleum, oil companies had tofind the most effective ways to store the energy source. In the oil industrys earliest days,wooden barrels served as storage vessels. But petroleum producers and sellers soonrealized that they needed a reliable, long-term, larger-capacity solution.

During the last two decades of the 1800s, riveted steel tanks were developed to store petroleum and, eventually, liquid chemical products. Whether it was used aboveground or underground, the riveted tank became the standard for storage when theneeded capacity was beyond a few barrels.

1.1 Standardizing tanks

The goal of standardizing tanks that held flammable and combustible liquids had greatappeal to tank owners, manufacturers, fire officials and insurers in the U.S. Severalorganizations with a stake in the manufacture and use of tanks began to address oil-storage safety issues in the early 1900s.

An association of steel tank manufacturers -- which later would become Steel Tank Institute (STI) -- was formed in 1916. Around the same time, a third-party testinglaboratory -- Underwriters Laboratories (UL) -- was developing its first safety standards

for atmospheric steel storage tanks. UL is a testing agency specializing in certifying product safety through listing procedures.

In 1922, UL unveiled its first atmospheric aboveground steel storage tank standard, UL142 (Steel Aboveground Tanks for Flammable and Combustible Liquids). In 1925, theagency published the first edition of its UL 58 document (Standard for SteelUnderground Tanks for Flammable and Combustible Liquids).

Another standard critical to the development of the storage tank industry preceded the ULdevelopments. It was created by a group that developed and promoted industry consensusstandards for protection of the public and firefighters from the hazards caused by fires.

The National Board of Fire Underwriters published NBFU 30 (circa 1904), which, as itstitle states, covered "Rules and Requirements for the Construction and Installation of Systems for Storing 250 Gallons or Less of Fluids Which at Ordinary Temperatures GiveOff Inflammable Vapors, as Recommended by its Committee of Consulting Engineers."

NBFUs codes and standards over time became the responsibility of the National FireProtection Association (NFPA), which modified the storage system standards code


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designation to NFPA 30L (published in 1913). Today that standard is known as NFPA 30(Flammable and Combustible Liquids Code), a document that was first published in1957. Many governmental bodies in the U.S. today reference the NFPA standard either

by legislation, statutes or ordinances to give local or regional officials an enforceablecode document. The NFPA code cites various construction standards written by UL and

STI, among other groups, as acceptable construction practices.

As the use of petroleum products escalated, the producers of hydrocarbons and thecompanies that install tanks created their own associations. The American PetroleumInstitute (API) was formed in 1919 and the Petroleum Equipment Institute (PEI) wasfounded in 1951. Both groups have developed several important tank system standardsand guidelines that are widely respected in many countries.

1.2 Effects of urbanization, industrialization

As the automobile industry began to grow, petroleum marketers had to adapt their

practices to enable mass distribution. Thus were born the first service stations in the U.S.,facilities that required minimal storage tank capacity. Compared to modern stations thatstore thousands of gallons underground, it was common for petroleum product in theearly 1900s to be stored within the dispenser itself.

Some fuel tanks were installed aboveground at gas stations, but many were installed below ground, for aesthetic purposes, particularly at public retail service stations.

As urban areas became densely populated leading to increased numbers of vehicles onthe road underground tanks became a more popular choice for fuel and chemicalstorage. The burial of USTs freed business owners to use real estate for other more-

productive purposes. From a public-safety perspective, USTs eliminated concerns aboutvehicle collisions or other damage that could result in spilled fuel.

1.3 The advent of welding

In the "early days" of steel tank production in the U.S., riveting was the most commonmethod of joining steel. Most tanks were small by todays standards, under 1,100 gallons(4,162 litres), though some were larger. During the 1920s and 1930s, arc weldingreplaced the riveting process for many steel fabricators, which led to higher quality tanks.

Galvanized steel sheet was often used in producing the tank. However, World War II

created a shortage of galvanized product in the U.S. Recognizing the scarcity faced byfabricators, UL began to allow the manufacture of tanks from black carbon steel.

The basic cylindrical design remained virtually unchanged for decades. However, in themid-1950s, product innovations began to surface. STI advocated placing the product lineon the bottom of a heating oil tank to prevent any accumulation of water. This design

breakthrough carried the water with the heating oil to the burner, which led toevaporation. And in 1956, STI issued its Midwest 56 Standard, a widely recognized


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approach to designing the size and location of openings along the top of an underground storage tank.

1.4 Progress in preventing corrosion

The control of corrosion on underground storage tanks in the U.S. has also relied heavilyon standards development. During the last 30 years, in particular, tank fabricators haveremarkably advanced the expected and actual service life of steel tanks.

1.4.1 Prior to mass concerns about corrosion

Manufacturers during the 1950s generally coated steel USTs with red lead primer or athin asphaltum-based paint. Such coatings dependably prevented atmospheric corrosion;however, they were nearly useless for protection against corrosion in many underground environments. Some entrepreneurs created magnesium-anode design kits, but they metwith no success in a market that knew little about corrosion.

The growth in motorized vehicles created more demand for service stations, which led todemand from petroleum marketers for greater capacity at each fueling site. By the early1960s, the average atmospheric-tank size had increased to nearly 4,000 gallons (15,137litres).

1.4.2 The dawn of anti-corrosion sentiment

The 60s also gave rise to a new material and new designs for underground flammableand combustible liquid tanks. The first design breakthrough was a non-metallic tank. Itwas made from fiber-reinforced plastic (FRP). Tank buyers hoped to avoid the inevitable

problem with steel underground storage tanks releasing product due to corrosion. At thattime, environmental concerns did not drive the new products development. Foremost onthe mind of petroleum marketers were inventory conservation and the cost to replace lost

product. However, from the chemical industrys standpoint, the FRP matrix posed compatibility questions that in the vast majority of cases were resolved with the use of carbon steel, or stainless steel, designs. Structural integrity and compatibility were two of the biggest hurdles that FRP tank producers had to overcome.

Tank owners began to realize that three underground storage tank options were available:replacing the tanks, closing the business or fuel facility, or upgrading to improved technology.

Some owners tried to address corrosion through internal lining, which first was used around 1962 for aboveground heating oil tanks. The technology eventually was applied toUSTs. The U.S. Environmental Protection Agency (EPA) in 1988 accepted lining as amethod to complement corrosion control requirements. Regulators mandated inspectionsat least once every 10 years.

Many systems also were upgraded in situ with an impressed-current design featuring


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the installation of rectifiers and special anodes to protect complete bare steel systems.

The steel industry paid close attention to the efforts to produce a non-metallic tank, as did major oil producers. So steel tank makers responded with their own research efforts focused on methods to make steel tanks corrosion resistant.

1.4.3 The baggie

One effort that preceded the debut of the FRP tank was to install the steel tank in a plasticwrap or "baggie". One major oil company had installed a number of baggie systems inthe state of Michigan as early as 1959. About 12 years later, steel tanks from thisinitiative were uncovered and found to be free of any corrosion. Preventing groundwater and corrosive-soil contact against the outer steel tank surface essentially eliminates acorrosion trigger.

During the next decade, the plastic baggie concept was commercialized for nationwide

steel tank production. As of 1970, more than 1,000 plastic-wrap tanks had been installed.Although this concept had merit, the plastic was quite thin and prone to tearing. Installersand manufacturers also discovered the difficulty of assuring a long-term seal between the

pieces of plastic.

The baggie had limitations, so STI developed a new approach a standard for covering asteel tank with a thick FRP coating. The concept was simple. If a non-metallic tank could

be installed to eliminate corrosion, why not coat the steel tank with that very samematerial?

1.4.4 The FRP coating

STI published the FRP laminate standard in 1968 and called it STI-LIFE. The standard actively existed for about five years. But fabricators stopped using it for the most part

because of aesthetics and cost. The glass strands were not always lying flat and parallel tothe steel. Equipment to produce the coating was relatively unsophisticated, unlike todaysmanufacturing processes in which the steel tank rotates while glass fibers and resin aresprayed onto the exterior.

Though the bulk of STI-LIFE fabricators dropped the product, several fabricatorscontinued to make FRP-coated steel tanks. A different standard was developed in 1987 torepresent this type of composite product. The new standard became known as ACT-

100, a tank that gained wide acceptance during the 1980s and 1990s because of adurable 100-mil coating applied through processes that eliminated the unsightly strandsthat plagued the STI-LIFE product. Each steel tank that combines glass and resin is tested in the factory with high-voltage holiday testers that will spark if any exposed steel isdiscovered.

1.4.4 The cathodic protection success


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During the mid-1960s, the US Steel Company recognized the threat of new materials for tanks, which could undermine its interest in maintaining steel as the material of choicefor storage applications. Faced with the non-metallic challenge, US Steel dedicated some

personnel from its research center to corrosion control for underground storage tanks.

The researchers came up with a notion pre-engineered protection against corrosion that would change the UST industry. The steel tank industrys greatest success followed the US Steel research, which led to development of a cathodically protected underground storage tank known as sti-P3. In 1969, the Steel Tank Institute unveiled the sti-P3design, which consisted of three major elements: good dielectric coating of the outer shell, galvanic magnesium anodes and electrical isolation of the tank from steel piping.The earliest coating was a coal-tar epoxy, which was significantly advanced from theindustrys prior products of choice. In addition to US Steel, Dow Chemical helped todevelop the sti-P3 design with Kennedy Tank & Manufacturing Co. of Indianapolis,Indiana, an STI member.

There were a number of improvements in the sti-P3 design during the 70s and 80s including the development of urethane coatings and enhanced methods of applying FRPas an external corrosion barrier. Magnesium anodes, attached to the tank by wire, werevirtually supplanted during that time by an innovative weld-on zinc anode design.

During those decades, STI also developed a national registration program. Manufacturers provided tank owners with a 30-year warranty against failure due to external corrosion.With the warranty came a strong quality assurance inspection program, which STIadministers on behalf of licensed manufacturers. Inspectors arrive at a tank shopunannounced and at random to verify that the fabricator is meeting STIs requirements.

The success of sti-P3 occurred while American attitudes about USTs were changingsignificantly.

1.4.6 Environmental and fire-safety awareness grows

Throughout the late 1970s, more and more media attention in the U.S. was focused onleaking underground storage tanks heightening the tank industrys emphasis onenvironmental protection. Many efforts were focused on integrity testing of the tank. Buttank-integrity testing was fairly new and had limited accuracy. Large leaks were easilynoticed, but small microscopic leaks were difficult to spot. This resulted in record-keeping improvements for monitoring inventory. Many of the major oil companies began

replacing their bare steel tanks with protected tank technology cathodically protected steel and non-metallic FRP. In some cases, existing tanks were retrofitted with an internallining, or a field-installed, impressed-current cathodic protection system. However, nonational standards existed for either approach.

By 1977, most members of the industry had become aware of leaking underground storage tanks. Fire codes, such as NFPA 30 and the Uniform Fire Code, introduced language into their respective codes mandating corrosion protection. But by current


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standards, fire codes in the late 1970s were lax. For instance, the codes said steel tankscould be cathodically protected, simply well coated, or not protected from corrosion at all

each of the three instances dictated by the soil corrosivity for the site at which the tank would be installed.

During the 1970s and 1980s, the pre-engineered sti-P3 approach became the leadingsteel underground storage tank built in America. Nearly 60 manufacturers across thenation were qualified and licensed to fabricate sti-P3 tanks, which were visuallydistinguished in the marketplace by zinc or magnesium anodes most commonly attached to the heads of the tanks. The anodes provided low levels of electrical current that would

prevent corrosion underground if the tanks coating should be slightly flawed, or damaged during installation.

1.4.7 Tank system performance

The sti-P3 system was designed to protection against external corrosion in virtually any

soil environment, regardless of corrosivity levels. Did it work?

STIs registration database shows that more than 250,000 sti-P3 tanks have beeninstalled across America to date. The technologys performance has been nearly flawless,according to a 1993 report by Tillinghast, a U.S.-based risk-management consulting firm.

Tillinghast contacted tank owners and installers to develop a representative sample of sti-P3 tanks in service. The firms survey of tank owners "covered over 3,000 sti-P3tanks, and the survey of tank installers covered over 5,000 sti-P3 installations," thereport said. "Of the 8,000-plus sti-P3 tanks, three instances of external corrosion werereported, representing a frequency of 0.04 percent. Only one of the three instances

involved a product release."

1.4.8 Regulatory setback

Despite this remarkable record of performance, the sti-P3 tank suffered in themarketplace after federal regulators in 1988 announced the technical requirements for UST systems.

To address a regulatory mandate for periodic monitoring of cathodic protection, STI in1988 developed the Watchdog program, which provided the services to owners of registered sti-P3 tanks. Watchdog technicians gathered the readings at tank sites using a

voltmeter and a copper/copper sulfate reference electrode and stored the information inhand-held computers that eventually were used to transfer test results to a centraldatabase. Watchdog program participants received reports for their files of cathodic

protection readings.

Prior to the Watchdog program, sti-P3 tank owners had been enabled to performcathodic protection monitoring with pre-engineered monitoring stations known asProtection Prover 1 (PP1) and PP2. After the Watchdog program, an improved model, the


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PP4 terminal, debuted on sti-P3 tanks in the early 1990s.

More than 90,000 Watchdog tests have been performed for STI by cathodic protectiontesters who have used the PP1, PP2 or PP4 monitoring stations.

1.5 The demand for secondary containment

Mass production of dual-walled steel tanks was rare during the 1970s and the early1980s. However, the tank-manufacturing industry sensed that a growing number of customers was searching for enhanced environmental protection.

In 1983, Steel Tank Institute formed a special strategic planning committee to addressseveral concerns with underground storage tanks, including secondary containment. Theregulatory landscape was changing. Government officials were starting to develop USTrequirements for secondary containment.

At that time, most double-wall tank designs provided 110% containment of the primarytank, which required channel or angle iron to separate the primary and secondary vessels.Each steel tank was independent capable structurally of standing by itself. STIdiscovered that German tank makers were already building to a double-wall design under a markedly different approach. STI members visited Europe and learned from theGerman experience, which led to the publication in 1984 of Americas first secondarycontainment standard.

STIs standard provides for an outer wall of steel to be intimately wrapped over the primary tank. The external wall can be a thinner gauge of steel. Due to the intimate wrap,the two walls act as a single structural unit, reducing the costs to build the tank. By

adding an interstitial monitoring port, the owner can detect leaks either manually or withspecial continuous monitoring equipment. This design enabled new technology to evolve.Electronic and mechanical means to detect liquids followed. STI members verified thatthe intimate wrap did not inhibit product or water introduced into the interstice fromfinding its way to the monitoring port.

1.6 Federal and state regulations

Many local, state and county officials by 1982 were addressing the growing problem of leaking underground storage tanks through enactment of regulations. In 1984, the U.S.Congress approved a law to regulate underground storage tanks. By that time, media

attention was reaching a peak

The congressional action led to development of a federal regulatory program. The federalgovernments technical requirements called for corrosion protection for tanks and piping,structural integrity, release detection, proper installation, corrective action and secondarycontainment for the storage and handling of hazardous materials other than petroleum

products.


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A key facet of the regulation was how the Environmental Protection Agency enabled newtechnology to become accepted, which was very important because new approaches toUST systems were surfacing rapidly. Speeding the advent of new tank systemtechnologies was the emergence of smaller, faster and more powerful computers that

provided new automated solutions, especially in leak detection and inventory control.

The tank and pipe industry also bred new technological approaches such as jacketed steeltanks and flexible piping.

A jacketed tank is an outer, non-metallic containment for a steel tank that also providescorrosion protection. The most prominent materials developed for secondary containmenthave been high-density polyethylene and fiber-reinforced plastic. Typically, thesesystems were shipped from the factory with a vacuum between the walls of the tank. The

jacketed steel tank offered several advantages lighter weight than a tank with two wallsof steel, and a lower cost. Flexible piping produced with a combination of chemicallyresistant plastic and elastomer attached to UST systems and eliminated leaks thattraditionally occurred from loose elbows and fittings on steel pipe.

Another noteworthy construction feature emerged as the EPA regulations gained prominence. Sumps and boxes were placed above the tank and under the dispenser tocatch releases from fittings and maintenance activities. Steel Tank Institute in 1986 wasthe first organization to develop a national sump design standard, known simply enoughas STI-86. This concept was designed to allow all fittings and important tank appurtenances to be clustered in one spot with the protection of secondary containment.This included the submersible turbine pump, vapor-recovery equipment, gauges, and fillopenings. The sump container was made from steel, and would "catch" any releases fromthe enclosed equipment. In addition, secondary containment pipe would terminate in thesump, where sensors would be mounted to detect releases from piping as well. The STI-

86 paved the way for a wave of tank-industry innovation. Within a few years, the STI-86 became obsolete replaced by comparatively lightweight polyethylene sump containers.

2. Present

2.1 A federal regulatory deadline

The U.S. regulatory program spurred significant changes in the tank industry. As noted above,

the last decade witnessed the emergence of many new UST system technologies and

trends. Manufacturers and system designers trotted out UST enhancements in advance of the December 22, 1998 EPA deadline for upgrading underground tank systems.

Many small service station operators used the EPA deadline as a reason to sell or shutter their fueling facilities. However, some tank owners embraced the new designs becausetheir businesses were committed to the use of underground storage for the long haul.And, increasing numbers of tank owners revisited the question of why petroleum and chemicals had to be stored underground.


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The 1990s unexpectedlyunveiled a completely ntrend extraordinarydemand for aboveground storage tanks. Because of

the negative headlinesassociated with expensiveUST cleanups -- includingcontaminated soils and water resources -- tank owners began to think seriously about theadvantages and disadvantages of owningan underground tank system. Many elected to

close their tanks. For those who had needed tanks for fueling vehicles, many begansending their drivers to a nearby retail service station.

ew

2.2 ASTs market impact

Tank-system owners began to study the advantages of an aboveground tank system. First,the owner/operator could see all of the tanks surfaces. There was no need to depend onother equipment or contractors to verify that a tank system was free from releases. Visualrelease detection pleases many tank operators because it is simple, cheap, convenient, and trustworthy. Second, the owner/operator did not have to meet the financial responsibilityrequirements of regulated UST systems. Third, the owner/operator didnt have to worry

about regulated, expensive soil clean-ups, which seemed to be constantly in the publiceye via local and national headlines. Finally, many owner/operators felt that aboveground tank systems were cheaper to install and less regulated (though that perception was oftenflawed). The new era of aboveground tanks was about to change the market (Figure 1).

But the storage question wasnt as simple as how to switch from underground toaboveground. Many local jurisdictions in the U.S. did not allow aboveground fuelingsystems. They followed various national fire codes that imposed severe restrictions uponASTs, or simply prohibited fuel storage aboveground for dispensing into motor vehicles.

Despite that, fleet owners and industrial firms saw tremendous benefit from owning

ASTs, as described above. The typical owner of a public-accessible retail service stationcontinued to prefer underground storage tanks (as did most fire inspectors) over often-unsightly and potentially unsafe aboveground tanks.

2.3 Fire code revisions and harmonization during the 90s

With the suddenly strong demand for aboveground tanks in the U.S., the codes needed tofind a way to allow the safe siting of aboveground fueling facilities at service stations.


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Major provisions were added to codes in the early 1990s, such as allowing:

An aboveground tank to be installed inside a concrete vault, whether the vault waslocated above or below grade.

Other tanks to be installed aboveground, including traditional UL 142 tanks, and

another new technology, fire-resistant tanks. Protected tanks that had to prevent an internal tank temperature increase of more

than 260o F (127o C) when the structure was exposed to a 2,000o F (1093 o C)two-hour fire and had to have features that resisted impacts from vehiclecollisions and bullets

Fire-resistant tanks with construction that would prevent:o Release of liquidso Failure of the supporting structureo Impairment of venting for a period of not less than two hours when tested

by a fire exposure that simulates a high intensity pool fire

As the fire codes proposed new language, environmental regulators also examined whatwould constitute safe operation of ASTs. One federal proposal, for example, called for ASTs to employ containment that would be impermeable for 72 hours. As such ideassurfaced for the first time, the shop-fabricated AST market saw a major change incustomer demand. Specifiers were asking for steel dikes (or tubs) within which a tank would be installed. Steel, an impermeable material, certainly met the requirements of thefederal proposal. But demand for integral double-wall ASTs also was growing.

By 1997, STI had developed a statistically valid database of insulated protected tanks and double wall F921 tanks. The insulated tank was called Fireguard the specification for

which was published in 1994. STIs data showed that fewer than 4 percent of these ASTswere installed at public retail service station facilities. Private fleet facilities were the primary and dominant users of aboveground tanks for fueling vehicles. Nearly two-thirdsof stored-product applications were for less flammable Class II or III liquids, such asdiesel, kerosene or lube oils.

3. FUTURE

3.1 The case for compartment tanks

More and more specifiers in the U.S. are calling for compartment tanks as a storage

solution. Compartmentalized designs whether double-wall or single-wall often provide dramatic savings to the tank owner. If a tank system needs to hold 20,000 gallons(75,686 litres) with three different products, its considerably less expensive to build and install one tank divided into three compartments than three USTs with the sameaggregate capacity. This reduces costs by providing only one secondary containment and one interstitial monitoring device, while substantially decreasing excavation costs. Thecompartmentalized trend has also carried over to the aboveground storage tank market.


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3.2 Maintenanceremains critical

The proper iof an underground

storage tank or anAST to meet code aregulatoryrequirementclearly defined byindustry groups and manufacturers.However, to assuefficient and safelong-term operatio

a proper AST maintenance program is essential. Tank operators must remove water fro

dikes (when applicable) and tanks on a regular basis. Storage systems will work best if subjected to a regular inspection plan for each component. Its best to repaint steelstructures and repair concrete components to assure containment. For underground tankswith cathodic protection, periodic monitoring of the corrosion-protection system isrequired by regulation in the U.S.

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3.3 Fewer USTs, but more secondary containment systems

From 1988 to 1998, the underground tank population in the United States fell by morethan 60 percent. The number of retail service stations also dropped dramatically fromover 207,000 in 1992 to fewer than 183,000 in 1998. The EPA regulations impact has

put many old single-wall tanks out of commission. It also changed significantly the mixof UST end users (Figure 2). And it has opened the markets eyes to the need for aggressive action to prevent contamination of soil or drinking-water supplies.Underground or aboveground, specifiers increasingly are calling for storage systems that

provide secondary containment to control leaks.

3.4 Ongoing change

Despite the many significant changes in prominent national codes, especially regardingASTs, new proposals surface every year. STI expects more revisions as regulatorsmonitor the safety performance of AST systems within their communities. The market-

driven developments of the last 30 years in the U.S. have redefined the industries that for decades made and used tanks the same way, day after day. Looking back and lookingforward, its clear that weve come a long way from the whiskey barrels and wash basinsof Titusville. But improvements are still on the horizon.

REPRINTED WITH PERMISSION FROM HANDBOOK OF STORAGE TANKSYSTEMS,

Marcel Dekker, Inc.


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STI Geyer Istoric